Field of the Invention
This invention relates to an inhalation training device for practicing of an inhalation process of a patient, and to an inhalation training system for practicing of an inhalation process of a patient.
Description of Related Art
Drugs which are to be inhaled constitute a preferred therapy for patients with asthma, a chronically obstructive pulmonary disease or other chronic or acute conditions or diseases of the respiratory tract.
So-called inhalers are used for inhalation of drugs. The most frequently used inhalers are pressurized metered-dose inhalers (pMDIs) and dry powder inhalers (DPIs). pMDIs were developed to supply a precise amount or dose of a drug in the form of a cloud of aerosol droplets to the lungs of the patient when the latter inhales. Dry powder inhalers are made such that when the patient inhales they supply a metered amount of dry pulverized particles to the lungs.
An alternative inhaler is shown e.g., in International Patent Application Publication WO 2008/151796 A1 and corresponding U.S. Patent Application Publication 2008/0314380. This inhaler delivers a metered dose of medication as a slow-moving, soft mist through a nozzle system without use of any propellant.
The effectiveness of drugs which are to be inhaled depends largely on the way the inhaler is used by the patient. Optimally, the correct amount of the drug travels to the desired regions of the lungs at the correct instant of time. Otherwise, the therapeutic effect is reduced and/or the risk of contrary effects is increased.
The literature contains numerous instances substantiating that many patients incorrectly use inhalers. Instruction of the patient with respect to a correct inhalation technique can improve the use of inhalers. In addition to written and oral instructions, practical exercises are helpful for this purpose.
Since inhalation generally proceeds subconsciously and develops over the course of a lifetime, it is however especially difficult for a patient to change his/her manner of inhaling in order to increase the effectiveness of a drug which is to be inhaled. Rather, it is known that many patients again use suboptimum inhalation even a short time after instruction. Therefore, repeated, preferably regular practicing (training) of inhalation and checking of it are recommended.
Inhalation training systems were developed for this purpose. Known inhalation training systems differ, among others, with respect to the inhalation model for which the patient is to be trained, with respect to the type of feedback to the patient (for example, acoustically or visually), with respect to the measured variable (for example inhaled volume, volumetric flow or flow rate or mass flow which is produced during inhalation, velocity of the inhaled particles during the inhalation process), with respect to sensors and actuators (for example mechanical, magnetic or electronic) and with respect to size, handling and costs. Some inhalation training systems use inhalers which are available on the market, while other inhalation training systems copy or emulate inhalers or parts of them.
European Patent Application Publication EP 1 993 642 A1 and corresponding U.S. Patent Application Publication 2009/0308387, which form the starting point of this invention, show an inhalation training device for practicing of an inhalation process of a patient. The known inhalation training device comprises a housing that is attachable to and detachable from a mouthpiece of an inhaler designed to provide a drug to the patient and a microphone adapted to measure the airflow occurring in the mouthpiece of the inhaler during an inhalation process of the patient. The known inhalation training device may further comprise data communication means for communication with, e.g., a computer or a device adapted to forward information from a monitoring device to a doctor or other person for analysis and evaluation.